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以松香、乙二醇为原料,合成松香乙二醇单酯,再与丙烯酸反应,得到松香乙二醇酯丙烯酯;然后在催化剂的作用下催化聚合得到聚松香乙二醇酯丙烯酯,再在催化剂作用下用过氧化氢氧化聚松香乙二醇酯丙烯酯。测定了聚松香乙二醇酯丙烯酯及其氧化物的比表面积、孔径、溶解性和差热等各种性能。BET法测定聚松香乙二醇酯丙烯酯的比表面、孔径分别为 0.3185 m2/g, 60~90 nm;聚松香乙二醇酯丙烯酯氧化物的比表面积、孔径分别为 9.3669 m2/g, 50~90 nm,说明所合成的聚合物为大孔树脂;聚松香乙二醇酯丙烯酯及其氧化物在乙醇中的溶解度分别为每 100 mL 0.0272 和 0.00482 g;聚松香乙二醇酯丙烯酯的交联度为 12.3%;两种聚合物失重 5% 时分别对应的温度为259.8和 307.8℃;在30~550℃的温度范围内样品没有明显的软化点;相对分子质量测定结果表明聚松香乙二醇酯丙烯酯氧化物的相对分子质量在 25000以上。 相似文献
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用非贵金属催化剂制备歧化松香的研究 总被引:5,自引:0,他引:5
在自己组装的常压鼓泡气体循环反应装置上,考察了非贵金属催化剂及反应条件对松香歧化反应的影响,制备出活性好,无脱羧现象的“蛋壳型”非贵金属催化剂,在220℃反应温度下,制备出符合工业要求的特级歧化松香(枞酸〈0.5%,去氢枞酸〉50%)取得了松香歧化用非贵金属催化剂小试制备的较佳结果。 相似文献
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以氢化松香(HR)和甲基丙烯酸缩水甘油酯(GMA)为原料,三乙胺为催化剂,对苯二酚为阻聚剂,通过溶剂法合成了氢化松香GMA酯化物(HG),采用单因素和正交试验对酯化反应条件进行优化。探讨了单体配比(n(HR)∶n(GMA))、催化剂用量、反应温度和时间对酯化物酸值和酯化率的影响。利用红外光谱对HG进行结构表征,热重分析对HG进行热稳定性测试。结果表明,成功合成了HG,且HG热稳定性较好,较佳工艺条件为n(HR)∶n(GMA)=1∶1. 2,催化剂三乙胺用量为氢化松香的0. 5 wt%,110℃反应4 h,HG酯化率达到95. 8%。在引发剂、交联剂和分散剂存在条件下,HG可与苯乙烯反应生成聚合物微球,得到的微球球形较好,且带有羟基基团。 相似文献
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针对目前制备松香季戊四醇酯的催化剂毒性较强或成本昂贵,且所需能耗大等问题,本文以高效、无毒、绿色环保、廉价的羧酸盐和碱性盐类化合物为催化剂催化松香和季戊四醇酯化反应合成松香季戊四醇酯,考察了催化剂种类和用量、n(松香)∶n(季戊四醇)、反应时间和反应温度等因素对酯化反应的影响,得出较佳的反应条件,即n(松香)∶n(季戊四醇)为1∶0.25、松香30.0g、催化剂硬脂酸锌为松香质量的0.20%、反应时间7h、反应温度250℃。在上述条件下,所得产物松香季戊四醇酯的酸值为18.07mg/g、软化点为94.7℃、色泽为9~10(铁钴法)。同传统催化剂氧化锌相比,在不使用其他助剂的情况下,所得产物色泽浅、软化点和酸值较低,且反应具有催化剂用量少、反应温度低、无需分离催化剂等优点。 相似文献
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歧化松香木薯淀粉酯的微波合成及表征 总被引:2,自引:0,他引:2
在微波辐照下,以吡啶为溶剂和催化剂,经歧化松香酰氯和木薯淀粉的O-酰化反应合成得到歧化松香木薯淀粉酯。探讨了各种因素对产物取代度的影响,用元素分析、FT-IR、SEM、TG-DTA和XRD对目标产物进行了分析和表征,并测试了目标产物的溶解性能、防水性能。结果表明,最佳合成条件为淀粉活化时间1.5 h,反应温度100℃,反应时间2.5 h,吡啶用量25 mL,歧化松香酰氯与淀粉葡萄糖单元羟基的摩尔比3∶1,微波功率800 W。淀粉经歧化松香酯化改性后,结晶度降低,热稳定性提高,溶解性得到改善,并具有良好的疏水性,有望在防水涂料和塑料中得到应用。 相似文献
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以骨架镍为催化剂制备氢化松香的研究 总被引:12,自引:0,他引:12
采用均匀设计的实验方法,确定松香在骨架镍上催化剂加氢制备氢化松香的最佳工艺条件是:温度为170℃,压力为5.0MPa,催化剂用量为占松香质量的5.0%,溶剂质量分数为50%,反应时间为100mi ,搅拌转速为600r/min。在消除外扩散影响的情况下,骨架镍显示出与贵金属钯/炭催化剂相似的活性,而且寿命长,重复使用10次催化活性基本保持不变。文中还介绍了间歇法生产氢松香具有投资少、生产灵活多变等优点。 相似文献
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以甲阶酚醛树脂为原料制备了酚醛泡沫,经高温热处理进而得到酚醛树脂基碳泡沫。通过FTIR、TGA、SEM、压缩强度及热导率检测等手段,分析研究了酚醛泡沫在高温热处理后结构与性能的变化情况。结果表明:氮气保护下,酚醛泡沫经高温处理后形成了以碳元素为主的碳泡沫;与酚醛泡沫相比,碳泡沫的表观密度、泡孔孔径较小,泡孔虽仍以闭孔结构为主,但是开孔结构明显增多;酚醛泡沫及碳泡沫的压缩强度和热导率都随着泡沫密度的增加而增大,另外同酚醛泡沫相比,碳泡沫的压缩强度和热导率均相对较高。 相似文献
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Kanako Kaji Iwao Yoshizawa Choji Kohara Kuniaki Komal Motoyoshi Hatada 《应用聚合物科学杂志》1994,51(5):841-853
Flame-retardant polyethylene foam was successfully obtained by grafting a vinyl phosphonate oligomer onto polyethylene foam of an open-cell type using a simultaneous radiation grafting technique. The foam was impregnated with the oligomer and irradiated in a nitrogen atmosphere with an electron beam. The grafted foam thus obtained was found to pass the three most severe flammability tests that have to be cleared when the foam is to be used for materials where high flame-retardant property is required. No hydrogen cyanide was detected in burning exhaust gas of the grafted foam. © 1994 John Wiley & Sons, Inc. 相似文献
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Skinless polymer foam was prepared by treating poly(methyl methacrylate) (PMMA) with supercritical carbon dioxide (scCO2). The film was immersed in scCO2 with ethanol to nucleate, and then incubated in a hot water bath to induce nuclear growth and to prepare skinless PMMA foam. The obtained polymer foam had a low density and cells were connected to each other to make channels through the skin layer. Low molecular weight PMMA formed skinless foam with larger cells through expansion. PMMA film containing tin meso-tetraphenyl porphyrin was also foamed with same procedure and the foam was used for photoinduced hydrogen evolution. A larger amount of hydrogen evolved from the photocatalyst on the skinless PMMA foam in comparison with the foam with skin. Enlargement of effective surface area of solid support and light scattering within the foam could enhance turnover number (TON) of photocatalyst. 相似文献
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Yoshiyuki Bando Takahiro Kuze Tatsuya Sugimoto Keiji Yasuda Masaaki Nakamura 《Korean Journal of Chemical Engineering》2000,17(5):597-599
The foam separation of metal in model wastewater is performed by using two different bubble columns in a continuous operation
mode. The equipment and operation conditions are changed, and the foam flow rate and metal concentration in foam flow are
measured. The foam flow ratio (the ratio of foam flow rate to the inlet one) increases with increasing gas velocity, with
decreasing liquid velocity, with decreasing foam layer height and with decreasing metal concentration in model wastewater.
Metal enrichment (the ratio of metal concentration in foam flow to that in inlet flow) shows the reverse tendencies. When
a draft tube is inserted in the bubbling layer, the foam flow rate decreases. The enrichment is strongly governed by the foam
flow ratio. Since the foam flow ratio is adjusted by means of the equipment and operation conditions, the metal concentration
in foam flow is controlled to be a desired value.
This paper was presented at The 5th International Symposium on Separation Technology-Korea and Japan held at Seoul between
August 19 and 21, 1999. 相似文献
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Crude oil properties significantly affect foam behavior that is important to foam application in enhanced oil recovery. This study focused on the comparison on foam behavior in the presence of light oil and heavy oil. Foamability and foam stability, the bubble size, and the film thickness as well as the configuration of oil drops were fully investigated. Final results indicated that both the heavy oil and light oil increased the foamability of sodium dodecyl sulfate but decreased that of the amphoteric surfactant imidazoline. The positive effect of both light oil and heavy oil on foam stability was reconfirmed. However, heavy oil was more favorable to foam stability. The light oil may shorten the foam half‐life but prolong the foam drainage half‐life. The heavy oil was more effective in reducing the foam size and increasing the foam uniformity compared with light oil. According to the micrograph of foam, light oil was emulsified into quite small oil droplets, filling the plateau borders and lamellas. The heavy oil, in the form of far larger oil droplets, was mainly distributed in plateau borders only. The larger oil droplets resulted in the more stable foam, which was verified. Moreover, light oil (oil B) performed well in thickening the foam film, as did the heavy oil (oil A). But for the lightest oil (oil C), a thinning effect on the film was detected. 相似文献
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起泡剂的起泡性能及使用浓度优选研究 总被引:1,自引:0,他引:1
起泡剂的起始发泡体积和泡沫稳定性是决定起泡剂起泡性能的两个重要因素,也是实际应用当中筛选起泡剂的重要指标.采用Ross-Miles法对13种不同类型起泡剂在常温下的起泡性能进行了评价.结果表明:不同类型起泡剂的起始发泡体积和泡沫稳定性具有显著的不同.不同起泡剂的起始发泡体积随浓度的增加而增大.当起泡剂浓度增加到0.5%时,起始发泡体积趋于稳定,由此确定起泡剂的最佳使用浓度为0.5%. 相似文献
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The purpose of this study is to develop a protective and thermally intelligent filler by optimizing the preparing conditions and the thermoresponsive property of PU foam. The specimens were polyurethane synthesized by a one step process with 4,4′‐diphenylmethane diisocyanate, polycaprolactone and 1,4‐butanediol. After dissolving the polyurethane in tetrahydrofuran, the polyurethane foam was manufactured by the salt leaching method. The appearance, compressive property, and thermal property of the manufactured foam as well as the shape memory effects were evaluated. In addition, air and water vapor permeabilities and the thermal insulation property were measured to examine the basic properties of the foam. The cell sizes of the completed foam were distributed in the range of 400–1,000 μm. The compressive stress of the foam was low in the initial compressive strain but increased dramatically above a compressive strain of 70%. However, the foam showed a very low capacity for compressive stress compared with an electrospun web or a film manufactured by using the identical shape memory polyurethane. The transition temperature of the foam was 30°C. The shape recovery and shape retention were 98% or higher. The foam, with a porous structure, was found to be generally good in both air and water vapor permeability. In the case of the foam that maintained its compressed shape below the transition temperature, these permeabilities of the foam decreased slightly, but not significantly. Because of the porous structure of the foam, the shape memory effect did not noticeably influence the permeability change with a change in temperature. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献